Process for producing tetrakis(Faryl)borate salts

ABSTRACT

The liquid ethereal medium or liquid hydrocarbyl medium of a solution or slurry of an alkali metal tetrakis( F aryl)borate is substituted with at least one halogenated hydrocarbon, without isolating the alkali metal tetrakis( F aryl)borate, to form a new slurry or solution. At least a portion of the new solution is mixed together with a salt selected from a) a protic ammonium salt, b) an onium salt, and c) a triarylmethyl salt, to produce a protic ammonium tetrakis( F aryl)borate, an onium tetrakis( F aryl)borate, or a triarylmethyl tetrakis( F aryl)borate.

TECHNICAL FIELD

[0001] This invention relates to a method for making organic cationtetrakis(^(F)aryl)borate salts from an alkali metaltetrakis(^(F)aryl)borate. When the organic cation is a protic ammoniumcation or a triarylmethyl cation, the tetrakis(^(F)aryl)borate salt isuseful as a cocatalyst for metallocene-catalyzed polymerization. Whenthe organic cation is an onium cation, the tetrakis(^(F)aryl)borate saltis useful as an initiator in the crosslinking of polyorganosiloxanes.

BACKGROUND

[0002] It has been found that, when dry, alkali metaltetrakis(^(F)aryl)borates are thermally sensitive. Alkali metaltetrakis(^(F)aryl)borates are also sensitive to shock. Thesesensitivities clearly indicate potential hazards in the handling andprocessing of such compounds. Because alkali metaltetrakis(^(F)aryl)borates are useful intermediates in the preparation oforganic cation tetrakis(^(F)aryl)borates, it would be very desirable tominimize or eliminate these sensitivity problems.

SUMMARY OF THE INVENTION

[0003] Surprisingly, it has been discovered that the presence ofsolvent, especially a halogenated hydrocarbon, mitigates both thethermal and shock sensitivity of alkali metal tetrakis(^(F)aryl)borates.Additionally, it has been found that the reaction time when formingtriarylmethyl tetrakis(^(F)aryl)borates from alkali metaltetrakis(^(F)aryl)borates is significantly reduced when operating inhalogenated hydrocarbons. In particular, the reaction of 20 grams ofpotassium tetrakis(pentafluorophenyl)borate with triphenylmethylchloride is complete in under twenty minutes in dichloromethane, ascompared to over ten hours for the same reaction on the same scale inhexane.

[0004] An embodiment of this invention is a process for producing proticammonium tetrakis(^(F)aryl)borate, an onium tetrakis(^(F)aryl)borate, ora triarylmethyl tetrakis(^(F)aryl)borate from a solution or slurry of analkali metal tetrakis(^(F)aryl)borate in a liquid ethereal medium orliquid hydrocarbyl medium. This process comprises substituting theliquid ethereal medium or liquid hydrocarbyl medium with at least onehalogenated hydrocarbon, without isolating the alkali metaltetrakis(^(F)aryl)borate, to form a new slurry or solution. At least aportion of the new slurry or solution is mixed together with a saltselected from a) a protic ammonium salt, b) an onium salt, and c) atriarylmethyl salt, to produce a protic ammoniumtetrakis(^(F)aryl)borate, an onium tetrakis(^(F)aryl)borate, or atriarylmethyl tetrakis(^(F)aryl)borate. The triarylmethyl cation hasthree aryl groups bound to a central carbon atom. The protic ammoniumcation has the formula [R₃NH]^(⊕), in which each R is independently ahydrocarbyl group containing up to about thirty carbon atoms, and theonium cation has the formula [ER_(n)]^(⊕), wherein E is an element ofany of Groups 15-17 of the Periodic Table, wherein each R isindependently a hydrocarbyl group containing up to about thirty carbonatoms, and wherein n is equal to the valence of E plus one. For labelingof the groups of the Periodic Table, see for example, the Periodic Tableappearing in Chemical & Engineering News, Feb. 4, 1985, 69, 26.

[0005] The borate anion has four fluorine-containing aryl groups, eachof which has bonded directly to an aromatic ring at least two fluorineatoms, or at least two perfluoro hydrocarbyl groups, or at least onefluorine atom and at least one perfluorohydrocarbyl group. It ispreferred that at least two fluorine atoms, or at least twoperfluorohydrocarbyl groups are bonded directly to an aromatic ring.Each position on the aromatic ring(s) of the ^(F)aryl group that is nota fluorine atom or a perfluorohydrocarbyl group is substituted by ahydrogen atom, a hydrocarbyl group, an alkoxy group, or a silyl group.The ^(F)aryl groups may be the same or different from each other; it ispreferred that all four ^(F)aryl groups are the same.

[0006] Further embodiments of this invention will be apparent from theensuing description and appended claims.

FURTHER DETAILED DESCRIPTION OF THE INVENTION

[0007] Liquid ethereal medium is comprised of one or more liquiddihydrocarbyl ethers, and may also include one or more liquidhydrocarbons, water, or mixtures thereof. Liquid hydrocarbyl medium iscomprised of one or more liquid hydrocarbons, and may also include oneor more liquid dihydrocarbyl ethers, water, or mixtures thereof.Typically, the alkali metal tetrakis(^(F)aryl)borate in a liquidethereal medium is in the form of a solution, while alkali metaltetrakis(^(F)aryl)borate in liquid hydrocarbyl medium is usually in theform of a slurry. Often, the alkali metal tetrakis(^(F)aryl)borate inliquid hydrocarbyl medium forms an oily layer at the bottom of thesolution when traces of ether and/or water are present.

[0008] The alkali metal tetrakis(^(F)aryl)borate may be a lithium,sodium, potassium, rubidium, or cesium tetrakis(^(F)aryl)borate.Preferably, the alkali metal of the alkali metaltetrakis(^(F)aryl)borate is lithium, potassium, or sodium; mostpreferably, the alkali metal is sodium or potassium. Most preferred asthe alkali metal is potassium; thus, the most preferred alkali metaltetrakis(^(F)aryl)borate is a potassium tetrakis(^(F)aryl)borate.

[0009] Throughout this document, the term “^(F)aryl group” shall beunderstood to mean, as described above, a fluorine-containing arylgroup, which has bonded directly to an aromatic ring at least twofluorine atoms, or at least two perfluorohydrocarbyl groups, or at leastone fluorine atom and at least one perfluorohydrocarbyl group. It ispreferred that at least two fluorine atoms or at least twoperfluorohydrocarbyl groups are bonded directly to an aromatic ring.Each position on the aromatic ring(s) of the ^(F)aryl group that is nota fluorine atom or a perfluorohydrocarbyl group is substituted by ahydrogen atom, a hydrocarbyl group, an alkoxy group, or a silyl group.The aromatic ring of the ^(F)aryl group may be, but is not limited to,benzene, naphthalene, anthracene, biphenyl, phenanthrene, or indene.Benzene is the preferred aromatic moiety. The perfluorohydrocarbylgroups include alkyl and aryl perfluorocarbons; suitableperfluorohydrocarbyl groups are, for example, trifluoromethyl,pentafluoroethyl, pentafluorophenyl, and heptafluoronaphthyl. Thehydrocarbyl groups of the aryl groups are preferably C₁ to C₁₈ alkylgroups or C₆ to C₂₀ aryl or aralkyl groups. Examples of suitablehydrocarbyl groups are methyl, ethyl, isopropyl, tert-butyl,cyclopentyl, methylcyclohexyl, decyl, phenyl, tolyl, xylyl, benzyl,naphthyl, and tetrahydronaphthyl. The alkoxy groups preferably have C₁to C₆ alkyl moieties. Some examples of alkoxy groups are methoxy,ethoxy, isopropoxy, methylcyclopentoxy, and cyclohexoxy. The silylgroups preferably have C₁ to C₁₈ alkyl groups or C₆ to C₂₀ aryl oraralkyl groups. Suitable silyl groups include trimethylsilyl,triisopropylsilyl, tert-butyl(dimethyl)silyl, tridecylsilyl, andtriphenylsilyl. Examples of ^(F)aryl groups that may be present on theborate moiety in this invention include 3,5-bis(trifluoromethyl)phenyl,2,4,6-tris(trifluoromethyl)-phenyl,4-[tri(isopropyl)silyl]-tetrafluorophenyl,4-[dimethyl(tert-butyl)silyl]-tetrafluorophenyl,4′-(methoxy)-octafluorobiphenylyl, 2,3-bis(pentafluoroethyl)-naphthyl,2-(isopropoxy)-hexafluoronaphthyl,9,10-bis(heptafluoropropyl)-heptafluoroanthryl,9,10-bis(p-tolyl)-heptafluorophenanthryl, and1-(trifluoromethyl)-tetrafluoroindenyl. It is preferred that at most twosubstituents on the ring of the aryl group are hydrocarbyl,perfluorohydrocarbyl, or alkoxy, while the rest of the substituents arefluorine atoms.

[0010] It is highly preferred to have ^(F)aryl groups in which the allof the substituents are fluorine atoms. Examples of such groups arepentafluorophenyl, 4-nonafluorobiphenylyl, 2-nonafluorobiphenylyl,1-heptafluoronaphthyl, 2-heptafluoronaphthyl, 7-nonafluoroanthryl,9-nonafluorophenanthryl, and analogous groups. The most highly preferredperfluoroaryl group is pentafluorophenyl; thus, the most highlypreferred borate is tetrakis(pentafluorophenyl)borate.

[0011] Halogenated hydrocarbons that may be used include, but are notlimited to, dichloromethane, dibromomethane, trichloromethane,bromochloromethane, dichlorodifluoromethane, 1,2-dichloroethane,1,2-dibromoethane, tetrachloroethane, 1-bromo-2-chloroethane,trichloroethylene, 1-bromopropane, (chloromethyl)cyclopropane,1-bromobutane, 1-bromo-2-ethylbutane, 1,1-dichloro-3,3-dimethylbutane,cyclobutyl chloride, neopentyl chloride, 1-bromo-5-chloropentane,cyclopentyl bromide, 1,6-dibromohexane, trans-1,2-dichlorocyclohexane,1-chloroheptane, 1,8-dichlorooctane, and mixtures of any two or more ofthe foregoing. Preferred halogenated hydrocarbons are dichloromethane,trichloromethane, and 1,2-dichloroethane; most preferred isdichloromethane.

[0012] The substituting of the liquid ethereal medium or liquidhydrocarbyl medium, in which the alkali metal tetrakis(^(F)aryl)borateis dissolved or slurried, with a halogenated hydrocarbon can beaccomplished by a variety of means. Typical methods include decantation,solvent exchange via distillation (not to dryness), gentle evaporation(not to dryness), and centrifugation. For example, most of the liquidethereal or hydrocarbyl medium may be decanted, followed by the additionof the halogenated hydrocarbon(s). If the two media are immiscible, theycan be allowed to separate, so that more of the liquid ethereal orliquid hydrocarbyl medium can be decanted. The key is that the alkalimetal tetrakis(^(F)aryl)borate is not isolated from solvent at any pointduring the substitution. Generally, a slurry of the the alkali metaltetrakis(^(F)aryl)borate in the halogenated hydrocarbon is formed. Thesubstitution can be conducted at any suitable temperature below theboiling point of the halogenated hydrocarbon, so long as the alkalimetal tetrakis(^(F)aryl)borate is not adversely affected.

[0013] The new slurry or solution, comprising the alkali metaltetrakis(^(F)aryl)borate in the halogenated hydrocarbon, is mixed with atriarylmethyl salt, protic ammonium salt, or onium salt.

[0014] The term “triarylmethyl cation” refers to carbocations which havethree aryl groups bound to a central carbon atom. The aryl groups of thetriarylmethyl cation have from six to about twenty carbon atoms, can bethe same or different, and can be substituted or unsubstituted. Examplesof suitable aryl groups include phenyl, tolyl, xylyl, naphthyl, and2-ethylnaphthyl; preferred are tolyl and phenyl; most preferred isphenyl. The most preferred triarylmethyl cation is a triphenylmethylcation. Many inorganic anions can be appropriate counterions for atriarylmethyl cation; examples of suitable inorganic anions includechloride, bromide, iodide, tetrafluoroborate, hexafluorophosphate, andthe like. Preferred inorganic anions are the halides, especiallychloride; thus, the preferred salt is triphenylmethyl chloride.

[0015] For the contacting of an alkali metal tetrakis(^(F)aryl)borateand a triarylmethyl salt, the halogenated hydrocarbon liquid medium ispreferably dry (in the sense of having minimal water present), and it ispreferred that the reaction is conducted in an inert atmospherecomprised of one or more inert gases, such as, for example, nitrogen,helium, or argon.

[0016] Protic ammonium salts of the tetrakis(^(F)aryl)borate can beformed from the alkali metal tetrakis(^(F)aryl)borate. These ammoniumcations have the general formula [R₃NH]

, wherein each R is independently a hydrocarbyl group containing up toabout thirty carbon atoms. R is preferably an aliphatic or aromatichydrocarbyl group; preferred hydrocarbyl groups include methyl andphenyl. Examples of suitable protic ammonium cations include, but arenot limited to, trimethylammonium, triethylammonium,cyclohexyl(dimethyl)ammonium, tri(n-octyl)ammonium,phenyl(dimethyl)ammonium, diphenyl(ethyl)ammonium, and triphenylammoniumcations. As described above for the triarylmethyl salt, many inorganicanions can be appropriate counterions for the protic ammonium cation.Again, the halides, especially chloride, are preferred inorganic anions;thus, the preferred salt is generally a protic ammonium chloride.

[0017] The protic ammonium salt can be formed shortly before reacting itwith the alkali metal tetrakis(^(F)aryl)borate; this is accomplished byreacting R₃N, wherein R is defined as for the protic ammonium cations,with a protic acid to form the protic ammonium cation. Preferred proticacids include hydrochloric acid, hydrobromic acid, hydroiodic acid,fluoboric acid, and hexafluorophosphoric acid; hydrochloric acid is aparticularly preferred protic acid. Preferably, the protic ammoniumcation is formed in aqueous solution. For the mixing of the proticammonium salt and alkali metal tetrakis(^(F)aryl)borate, the exclusionof water is not necessary.

[0018] Other salts, generally referred to as onium salts, can be reactedwith the alkali metal tetrakis(^(F)aryl)borate to yield thecorresponding onium tetrakis(^(F)aryl)borate. Onium cations are definedby the formula [ER_(n)]^(⊕), wherein E is an element of any of Groups15-17 of the Periodic Table, each R is independently a hydrocarbyl groupcontaining up to about thirty carbon atoms, and n is equal to thevalence of E plus one. R is preferably an aliphatic or aromatichydrocarbyl group. As an example of n, when E is sulfur, which has avalence of two, n is three. As described previously for both thetriarylmethyl salts and the protic ammonium salts, many inorganic anionsmay be appropriate counterions for the onium cation. Preferred inorganicanions are the halides, especially chloride; thus, the preferred salt isgenerally an onium chloride. To form the oniumtetrakis(^(F)aryl)borates, standard cation exchange methods can be used.Examples of suitable onium salts include, but are not limited to,diphenyliodonium chloride, tris(p-tolyl)sulfonium bromide, andtetraethylphosphonium chloride.

[0019] Generally, the alkali metal tetrakis(^(F)aryl)borate and thetriarylmethyl salt, protic ammonium salt, or onium salt are mixedtogether at room temperature. Mixing at room temperature is preferredbecause the yield of triarylmethyl, protic ammonium, or oniumtetrakis(^(F)aryl)borate is often much higher than when the mixture isheated. Some heat may be produced during the course of the reaction,raising the temperature of the mixture. The mixture may be heated,provided that the temperature does not exceed the thermal decompositiontemperature of the product of the reaction. Heating during contacting ofalkali metal tetrakis(^(F)aryl)borate and the triarylmethyl, proticammonium, or onium salt is preferred when a faster reaction rate isdesired. Agitation of the reaction mixture is usually necessary for thereaction to proceed.

[0020] The contact time for alkali metal tetrakis(^(F)aryl)borate andthe protic ammonium salt or onium salt is preferably from about fifteenminutes to about eight hours; more preferred is a time in the range offrom about twenty minutes to about six hours. For mixing the alkalimetal tetrakis(^(F)aryl)borate and the triarylmethyl salt, the contacttime at room temperature is preferably in the range of from about twentyminutes to about twenty-four hours, and more preferably is in the rangeof from about one hour to about twelve hours. A contact time for alkalimetal tetrakis(^(F)aryl)borate and the triarylmethyl salt when heatingin the range of from about thirty minutes to about twenty hours ispreferred; a more preferable range is from about one hour to aboutfifteen hours; highly preferred is a contact time in the range of fromabout two hours to about twelve hours.

[0021] Experiments were performed on dry (solvent-free) alkali metaltetrakis(^(F)aryl)borates. All materials were tested at “standard”conditions (drop height=100 cm; drop weight=5 kg). Four runs with sodiumtetrakis(pentafluorophenyl)borate were performed. A black soot-like charremained in the test cell after testing. Results are summarized inTable 1. TABLE 1 Trial Decomposed Observations 1 Yes Residue was mostlydiscolored (grey/black). No smoke or spark observed. 2 Yes Small amountof smoke produced upon impact. Residue was completely discolored(gray/black). 3 Yes Residue was completely discolored (grey/black). Nosmoke or spark observed. 4 Yes Sparks and smoke observed upon impact.Black soot-like char residue.

[0022] The following example is presented for purposes of illustration,and is not intended to impose limitations on the scope of thisinvention.

EXAMPLE

[0023] Toluene (0.35 g) was added to 0.72 g of KB(C₆F₅)₄, which resultedin formation of a wet cake. The wet cake could not be stirred. Additionof CH₂Cl₂ (2.1 g) to the wet cake resulted in a slurry which wasstirrable. Trityl chloride (Ph₃CCl; 0.33 g, 120 mol %) was added slowlywith stirring into the slurry, forming deep-red Ph₃CB(C₆F₅)₄. Theslightly exothermic reaction was completed in about 1 minute. KCl wasformed as a side product. The KCl was collected by filtration; thefilter cake was rinsed with 2.0 g of CH₂Cl₂. The resultant solution ofPh₃CB(C₆F₅)₄ weighed 4.5 g, for a concentration of 20 wt %. Evaporationof ˜1.0 g of CH₂Cl₂ gave a 26 wt % of Ph₃CB(C₆F₅)₄.

[0024] Hexane (˜4.0 g) was added slowly to the Ph₃CB(C₆F₅)₄/CH₂Cl₂solution at 25° C. with fast stirring. A red oily layer was observed atfirst; this solidified within 10 minutes and coated the flask wall.After stirring for 1 hour at 25° C., all of the solids came off theflask wall to form fine yellow Ph₃CB(C₆F₅)₄ product. This yellow solidwas collected by filtration on a coarse frit and then rinsed once withhexane (3.0 g). NMR analysis (internal standard method) of purge-driedB4 solids showed a 99+% purity. The yield was at least 89%.

[0025] It is to be understood that the reactants and components referredto by chemical name or formula anywhere in the specification or claimshereof, whether referred to in the singular or plural, are identified asthey exist prior to coming into contact with another substance referredto by chemical name or chemical type (e.g., another reactant, a solvent,or etc.). It matters not what preliminary chemical changes,transformations and/or reactions, if any, take place in the resultingmixture or solution or reaction medium as such changes, transformationsand/or reactions are the natural result of bringing the specifiedreactants and/or components together under the conditions called forpursuant to this disclosure. Thus the reactants and components areidentified as ingredients to be brought together in connection withperforming a desired chemical reaction or in forming a mixture to beused in conducting a desired reaction. Accordingly, even though theclaims hereinafter may refer to substances, components and/oringredients in the present tense (“comprises”, “is”, etc.), thereference is to the substance, component or ingredient as it existed atthe time just before it was first contacted, blended or mixed with oneor more other substances, components and/or ingredients in accordancewith the present disclosure. Whatever transformations, if any, thatoccur in situ as a reaction is conducted is what the claim is intendedto cover. Thus the fact that a substance, component or ingredient mayhave lost its original identity through a chemical reaction ortransformation during the course of contacting, blending or mixingoperations, if conducted in accordance with this disclosure and with theapplication of common sense and the ordinary skill of a chemist, is thuswholly immaterial for an accurate understanding and appreciation of thetrue meaning and substance of this disclosure and the claims thereof.

[0026] Each and every patent or other publication referred to in anyportion of this specification is incorporated in toto into thisdisclosure by reference, as if fully set forth herein.

[0027] This invention is susceptible to considerable variation in itspractice. Therefore the foregoing description is not intended to limit,and should not be construed as limiting, the invention to the particularexemplifications presented hereinabove. Rather, what is intended to becovered is as set forth in the ensuing claims and the equivalentsthereof permitted as a matter of law.

1. A process for producing protic ammonium tetrakis(^(F)aryl)borate, anonium tetrakis(^(F)aryl)borate, or a triarylmethyltetrakis(^(F)aryl)borate from a solution or slurry of an alkali metaltetrakis(^(F)aryl)borate in a liquid ethereal medium or a liquidhydrocarbyl medium, which comprises i) substituting said liquid etherealmedium or liquid hydrocarbyl medium with at least one halogenatedhydrocarbon, without isolating the alkali metaltetrakis(^(F)aryl)borate, to form a new slurry or solution; and ii)mixing together at least a portion of said new slurry or solutionproduced in i) with a salt selected from a) a protic ammonium salt,wherein the protic ammonium cation has the formula [R₃NH]⊕, in whicheach R is independently a hydrocarbyl group containing up to aboutthirty carbon atoms, b) an onium salt, wherein the onium cation has theformula [ER_(n)]^(⊕), wherein E is an element of any of Groups 15-17 ofthe Periodic Table, wherein each R is independently a hydrocarbyl groupcontaining up to about thirty carbon atoms, and wherein n is equal tothe valence of E plus one, and c) a triarylmethyl salt, wherein thetriarylmethyl cation has three aryl groups bound to a central carbonatom; wherein each of the ^(F)aryl groups is a fluorine-containing arylgroup, each of which has bonded directly to an aromatic ring at leasttwo fluorine atoms, or at least two perfluorohydrocarbyl groups, or atleast one fluorine atom and at least one perfluorohydrocarbyl group. 2.A process according to claim 1 wherein said halogenated hydrocarbon isdichloromethane, trichloromethane, or 1,2-dichloroethane.
 3. A processaccording to claim 2 wherein said halogenated hydrocarbon isdichloromethane.
 4. A process according to claim 1 wherein said alkalimetal tetrakis(^(F)aryl)borate is a sodium or potassiumtetrakis(^(F)aryl)borate.
 5. A process according to claim 4 wherein saidalkali metal tetrakis(^(F)aryl)borate is a potassiumtetrakis(^(F)aryl)borate.
 6. A process according to claim 1 wherein saidalkali metal tetrakis(^(F)aryl)borate is a sodium or potassiumtetrakis(^(F)aryl)borate, and wherein said halogenated hydrocarbon isdichloromethane, trichloromethane, or 1,2-dichloroethane.
 7. A processaccording to claim 1 wherein the aromatic ring of said ^(F)aryl group isa phenyl ring.
 8. A process according to claim 1 wherein all of thepositions on said aromatic ring(s) of said aryl group are substituted byfluorine atoms.
 9. A process according to claim 8 wherein thetetrakis(^(F)aryl)borate is tetrakis(pentafluorophenyl)borate.
 10. Aprocess according to claim 9 wherein the alkali metaltetrakis(^(F)aryl)borate is sodium tetrakis(pentafluorophenyl)borate orpotassium tetrakis(pentafluorophenyl)borate.
 11. A process according toclaim 1 wherein the alkali metal tetrakis(^(F)aryl)borate is sodiumtetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, and wherein said halogenatedhydrocarbon is dichloromethane, trichloromethane, or 1,2-dichloroethane.12. A process according to claim 11 wherein the alkali metaltetrakis(^(F)aryl)borate is potassium tetrakis(pentafluorophenyl)borate,and wherein said halogenated hydrocarbon is dichloromethane.
 13. Aprocess according to claim 1 wherein said salt is a protic ammoniumsalt.
 14. A process according to claim 13 wherein at least one R groupof said protic ammonium cation is a phenyl group.
 15. A processaccording to claim 13 wherein the protic ammonium cation is aphenyl(dimethyl)ammonium cation.
 16. A process according to claim 13wherein the protic ammonium cation is a tri(n-octyl)ammonium cation. 17.A process according to claim 1 wherein the alkali metaltetrakis(^(F)aryl)borate is sodium tetrakis(pentafluorophenyl)borate orpotassium tetrakis(pentafluorophenyl)borate, and wherein said salt is aprotic ammonium salt.
 18. A process according to claim 17 wherein atleast one R group of said protic ammonium cation is a phenyl group. 19.A process according to claim 17 wherein the protic ammonium cation is aphenyl(dimethyl)ammonium cation.
 20. A process according to claim 17wherein the protic ammonium cation is a tri(n-octyl)ammonium cation. 21.A process according to claim 1 wherein the alkali metaltetrakis(^(F)aryl)borate is sodium tetrakis(pentafluorophenyl)borate orpotassium tetrakis(pentafluorophenyl)borate, wherein said halogenatedhydrocarbon is dichloromethane, trichloromethane, or 1,2-dichloroethane,wherein said salt is a protic ammonium salt, and wherein the proticammonium cation is a phenyl(dimethyl)ammonium cation.
 22. A processaccording to claim 1 wherein the alkali metal tetrakis(^(F)aryl)borateis sodium tetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, wherein said halogenated hydrocarbonis dichloromethane, trichloromethane, or 1,2-dichloroethane, whereinsaid salt is a protic ammonium salt, and wherein the protic ammoniumcation is a tri(n-octyl)ammonium cation.
 23. A process according toclaim 1 wherein said salt is an onium salt.
 24. A process according toclaim 23 wherein at least one R group of said onium cation is a phenylgroup.
 25. A process according to claim 22 wherein all of the R groupsof said onium cation are the same.
 26. A process according to claim 24wherein said onium salt is a diphenyliodonium salt.
 27. A processaccording to claim 1 wherein the alkali metal tetrakis(^(F)aryl)borateis sodium tetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, and wherein said salt is an oniumsalt.
 28. A process according to claim 27 wherein at least one R groupof said onium cation is a phenyl group.
 29. A process according to claim27 wherein said onium salt is a diphenyliodonium salt.
 30. A processaccording to claim 1 wherein the alkali metal tetrakis(^(F)aryl)borateis sodium tetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, wherein said halogenated hydrocarbonis dichloromethane, trichloromethane, or 1,2-dichloroethane, whereinsaid salt is an onium salt, and wherein said onium salt is adiphenyliodonium salt.
 31. A process according to claim 1 wherein saidsalt is a triarylmethyl salt.
 32. A process according to claim 31wherein at least one aryl group of said triarylmethyl cation is a phenylgroup.
 33. A process according to claim 32 wherein the triarylmethylcation is a triphenylmethyl cation.
 34. A process according to claim 1wherein the alkali metal tetrakis(^(F)aryl)borate is sodiumtetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, and wherein said salt is atriarylmethyl salt.
 35. A process according to claim 34 wherein at leastone aryl group of said triarylmethyl cation is a phenyl group.
 36. Aprocess according to claim 34 wherein the triarylmethyl cation is atriphenylmethyl cation.
 37. A process according to claim 1 wherein thealkali metal tetrakis(^(F)aryl)borate is sodiumtetrakis(pentafluorophenyl)borate or potassiumtetrakis(pentafluorophenyl)borate, wherein said halogenated hydrocarbonis dichloromethane, trichloromethane, or 1,2-dichloroethane, whereinsaid salt is a triarylmethyl salt, and wherein the triarylmethyl cationis a triphenylmethyl cation.
 38. A process according to claim 37 whereinthe alkali metal tetrakis(^(F)aryl)borate is potassiumtetrakis(pentafluorophenyl)borate, and wherein said halogenatedhydrocarbon is dichloromethane.
 39. A process according to claim 1wherein said at least a portion of alkali metal tetrakis(^(F)aryl)borateand said salt are at room temperature when mixed together.